The unknown is general, it not restricted to problems about a particular subject-matter. The problem can be algebraic, geometric, mathematical or nonmathematical [1]}.
In this paper, we focus on the topic of Probability as a case study.
To facilitate model training, we created a dataset, ProbUNK, containing Probability problems labeled with their unknown(s).
Figure REF  shows example problems from ProbUNK.
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